The complicated construction conditions

the small volume and irregular shape of the frozen wall are the characteristics of freezing reinforcement for shield junction in soft soil stratum. According to a freezing reinforcement project of shield junction in Shanghai

the model test based on similarity theory is conducted. Some conclusions are drawn through analyzing temperature data measured in the test. Firstly

under the condition of constant temperature on the inner surface of shield shell

the average expansion speed of the frozen soil inside the freezing-pipes is about 1.5 times that of outside the freezing-pipes. And the average temperature of the inside frozen wall is about 1.9 times that of the external frozen wall after 28 hours

when the temperature at the interface of shield and soil is about ?20 °C. Secondly

with a superposition of freezing-pipes

little difference appears at the beginning

and then similar variation for the temperature occurs in main plane and interface of the frozen wall during the freezing process. Thirdly

the freezing effect of the inner freezing-pipes on the outside soil is insignificant due to the temperature shielding of outside freezing-pipes

which leads to identical frozen wall thickness in the case of different freezing tube spaces and multiple freezing pipes crossing. Little difference in temperature distribution is found inside the frozen wall. The research results indicate a similar shape of the frozen wall to the layout of the outside freezing pipes during freezing process

and unchanged thickness and average temperature of frozen wall in 28 hours.